Deep in the forest, far from any human contact, there lives a child named Ryouma Takebayashi. He engages in the rather strange hobby of keeping various types of slimes as pets. Furthermore, despite his young age, he has a sturdy physique and good compatibility for magic. All of this is because, having endured much hardship in his previous life, three gods grace Ryouma with a second chance to pursue one goal: savor the wonders of life. After three years of comfortable solitude pass by, Ryouma meets people that will change his current life forever. When he encounters and helps some soldiers tend to their wounded comrade, the group convinces him to accompany them to visit the nearby town's ducal family. Ryouma agrees and soon embarks on a journey to explore the vast world beyond his home.

Despite standing at the zenith as the strongest exorcist, Haruyoshi Kuga sought even greater power, which led to his demise at the hands of those who envied his might. As he draws his last breath, he casts a spell that allows him to reincarnate and swears to become more cunning, hoping that all his efforts will prove useful in his next life. Haruyoshi is soon reborn in another world as Seika Lamprogue, an illegitimate son of a noble family that prides itself on magic. However, his new family largely ignores him due to his lineage and magic deficiency. Nevertheless, the unbothered Seika leverages the knowledge from his previous life to make numerous valuable allies. As he begins to explore the true limits of his abilities, Seika must also be wary of the consequences that tarnished his past and avoid repeating the same mistakes.

World-class medical researcher Kanji Yakutani lost his little sister to a tumor years ago due to ineffective treatment. To honor her legacy, he has dedicated his research to developing new medications for such conditions. But as fate would have it, he overworks himself and passes away at the age of 31, only to be given a second chance at life in another world. When he wakes up, Kanji finds himself in the body of a 10-year-old boy named Falma de Médicis, the son of an esteemed family of medical practitioners in the Sain Fleuve Empire. Bearing the mark of a deity's divine blessing, Falma is capable of performing a unique divine art, allowing him to create and reduce any substance with the knowledge of its chemical properties. After reading through some pharmacology books, Falma realizes that this world is operating on similar medical practices as in ancient times. He also learns that medicine is an exclusive privilege to the nobility, depriving commoners of proper medical care. Using the knowledge from his past life and the divine abilities granted to him, Falma resolves to make medicine available to those who need it—irrespective of class.

During the final years of his life, Hiraku Machio remained confined to a hospital bed with a terminal illness until he finally passed away. Taking pity on the unfair life he lived, a god decides to reincarnate Hiraku in another world where he can live as he pleases. Wanting to try farming in this new life, he is bestowed with an all-in-one Almighty Farming Tool that can transform into any useful implement he wishes. Hiraku is then transported to a forest seemingly far from civilization. Here, he plans to build and farm everything from scratch—gradually developing the lifeless area into a thriving new society.